The Best HIIT Workouts to Burn Calories & Build Muscle

Who doesn’t want to burn away extra fat and build some nice lean muscle before the weather warms up? Fortunately, you don’t have to quit your job or cancel on your family and friends to find time to get fit. A popular workout format can help you sizzle away the fat and get those sleek muscles you’ve always wanted. The catch? You’re going to have to be willing to push yourself hard. HIIT workouts are all about ramping up the intensity to give you the biggest fitness return for your time. This workout modality is so effective that the American College of Sports Medicine named HIIT the top fitness trend in 2020.

Keep reading to learn about what is a HIIT workout and to check out some of the best HIIT workouts.

What Is a HIIT Workout?

Intensity is the name of the game when it comes to high-intensity interval training or HIIT. This workout format is defined by bursts of intense exercise followed by a short amount of rest. Rinse and repeat. Most HIIT workouts last between five and 20 minutes and include several rounds of three to six exercises. The work-to-rest ratio can vary, but 1:1 is a popular format. For example, you’ll often see HIIT workouts designed with a 30 seconds “on”/30 seconds “off” ratio. (Getting a little confused? Not to worry. At the bottom of this article, you’ll find five great HIIT workouts to try.)

The beauty of HIIT workout plans is that you can swap exercises in and out so that every HIIT workout routine is unique and interesting. You can also adapt your workout to match your fitness goals. By including lots of cardio elements, you can create a HIIT cardio workout. Likewise, grab some weights, and you can build a strength-training HIIT workout.

The true heart of any HIIT routine is to work really hard during the “on” phase. Try to shoot for 70% – 85% of your max heart rate, or MHR. (A quick way to find your MHR is to deduct your age from 220.) Fitness watches and smartwatches can track your heart rate for you, which can help you know if you need to speed up or slow down during your workout.

Why Is a HIIT Workout Plan So Effective?

The truth is that any time you exercise, whether you walk, sprint, or lift weights, your body will burn extra calories compared to being sedentary. You’ll also become fitter. However, different types of exercises and workout formats have proven to be more effective than others when it comes to burning fat and building muscle.

Increasing the intensity of your workouts forces your cardiovascular system to work harder, which means you’ll burn a greater number of calories in a shorter amount of time. Research has found that HIIT workouts also help to improve your VO2 max, which is a measure of “how much oxygen your body can absorb and use during exercise,” according to Healthline.

Additionally, new research is discovering that lifting super heavy isn’t necessarily the only way to increase your muscle mass. Instead, lifting a moderate weight and approaching failure (a point at which you cannot perform another rep) can also improve muscular endurance and help you build lean muscles. Adding resistance movements into your HIIT workout gives you the opportunity to bank a high amount of lifting volume in a short amount of time.

High-intensity workouts can also put your body into EPOC, or excess post-exercise oxygen consumption. Yes, this is a fancy term, but it basically means that your body will need to work hard after your workout to restore your body’s normal levels of oxygen. This, in turn, means your body will keep working hard and burning calories even after your workout is complete.

Finally, one of the most important things that makes HIIT workouts so effective is that they’re short. You can put yourself through a brutal HIIT workout in 15 minutes. Add in a 10-minute warmup and 5-minute cooldown, and you can be in and out of the gym in 30 minutes while giving your muscles and heart an amazing workout. Shorter workouts are more realistic for everyday exercisers and make it more likely that you’ll stick to your workout routine in the long run.

How to Make HIIT Workout Plans Easier

Fitness purists will insist that a HIIT workout must be performed at 70% – 85% of your max heart rate and must have close to a 1:1 work-to-rest ratio; otherwise, you’re just doing interval training. However, many exercisers prefer not to push themselves to that level or may not have the physical capacity to do so.

That’s fine! If you are a new exerciser, dealing with an injury, or simply prefer to breathe a little easier during your fitness time, you can still do HIIT-inspired workouts. To make a HIIT workout easier, you can:

• Move a little slower and focus on a target 60% – 70% max heart rate
• Add more rest. Try a 20 seconds “on,” 40 seconds “off” format
• Cut out the last exercise from the routine
• Perform fewer rounds

Remember, any time you move, you’re doing your body a favor. If you are tired at the end of the workout, you did something right. It’s more important to stay safe and perform a workout that you are comfortable with than to stick to any strict definitions.

How to Make Your HIIT Workout Plans More Challenging

Are you an advanced exerciser who wants to push yourself to the max? Maybe you need to add some extra power to your HIIT. The faster and harder you go, the stronger you’ll get. To make your HIIT workouts more difficult:

• Don’t slow down. Try to maintain the same pace from start to finish during each movement
• Decrease your rest time. See if you can handle a 40 seconds “on” 20 seconds “off” format
• Perform active rest during your “off” periods, such as jogging in place
• Add another round to your workout

Five Best HIIT Cardio Workouts

Ready to actually give a HIIT workout routine a try? Below are five different HIIT sample workouts. Remember, there are many ways to make the workouts more or less challenging, and you can always swap in a different exercise if you don’t know an exercise or don’t have the right equipment or the space.

Recommended format: Three rounds, 30 seconds on, 30 seconds off

1. No-Equipment HIIT Workout

• Pushups
• Mountain climbers
• Sit-ups
• Air squats
• High knees in place

(Check out even more HIIT workouts you can do at home.)

2. Outdoor HIIT Workout

• Sprints
• Burpees
• Crab walks
• Plank knee crunch
• Jumping lunges

3. Gym HIIT Workout I

• Kettlebell swings (Moderate weight)
• Lunges with dumbbells (Light or moderate weight)
• Russian twist with dumbbell (Light or moderate weight)
• Burpees
• Goblet squats with kettlebell (Moderate weight)

4. Gym HIIT Workout II

• Jump rope (More challenging: Double-unders)
• Bar hanging knee-ups (More challenging: Toes-2-bar)
• Burpee and jump to tap pull-up bar (More challenging: Burpee pull-ups)
• Power cleans with barbell (Moderate weight)
• Push-press with empty barbell

5. Gym HIIT Workout III

• Front squats with empty barbell
• Pull-ups (Easier: Jumping pull-ups or banded pull-ups)
• V-Ups (Easer: Crunches)
• Mountain climbers
• Box jumps (no weight) or step-ups with dumbbells (Light weight)

Try a HIIT Workout Routine Today

Now you’ve got five great HIIT workouts to try, including workouts you can do at home or outdoors. If you’re new to exercising, it’s okay to start slow. As your cardiovascular endurance and muscular endurance improve, you can push a little harder each week. Not sure if you’re ready to do a HIIT workout on your own? Check your gym’s group fitness classes. Most gyms offer a range of cardio and strength-training classes and many also offer interval or HIIT training classes. To get a more customized training routine for your goals, consider hiring a personal trainer.